Gas turbine engine and fuel injection system

ABSTRACT

One embodiment of the present invention is a unique gas turbine engine. Another embodiment is a unique fuel injection system for a gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines and fuel injection systems for gas turbine engines. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of U.S. Provisional PatentApplication No. 61/427,726, filed Dec. 28, 2010, entitled GAS TURBINEENGINE AND FUEL INJECTION SYSTEM, which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to gas turbine engines, and moreparticularly, to fuel injection systems for gas turbine engines.

BACKGROUND

Gas turbine engines and fuel injection systems for gas turbine enginesremain an area of interest. Some existing systems have variousshortcomings, drawbacks, and disadvantages relative to certainapplications. Accordingly, there remains a need for furthercontributions in this area of technology.

SUMMARY

One embodiment of the present invention is a unique gas turbine engine.Another embodiment is a unique fuel injection system for a gas turbineengine. Other embodiments include apparatuses, systems, devices,hardware, methods, and combinations for gas turbine engines and fuelinjection systems for gas turbine engines. Further embodiments, forms,features, aspects, benefits, and advantages of the present applicationwill become apparent from the description and figures provided herewith.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawingswherein like reference numerals refer to like parts throughout theseveral views, and wherein:

FIG. 1 schematically illustrates some aspects of a non-limiting exampleof a gas turbine engine in accordance with an embodiment of the presentinvention.

FIG. 2 depicts some aspects of a non-limiting example of combustionsystem in accordance with an embodiment of the present invention.

FIG. 3 depicts some aspects of a non-limiting example of a fuelinjection system in accordance with an embodiment of the presentinvention.

DETAILED DESCRIPTION

For purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings, and specific language will be used to describe the same.It will nonetheless be understood that no limitation of the scope of theinvention is intended by the illustration and description of certainembodiments of the invention. In addition, any alterations and/ormodifications of the illustrated and/or described embodiment(s) arecontemplated as being within the scope of the present invention.Further, any other applications of the principles of the invention, asillustrated and/or described herein, as would normally occur to oneskilled in the art to which the invention pertains, are contemplated asbeing within the scope of the present invention.

Referring to the drawings, and in particular FIG. 1, a non-limitingexample of a gas turbine engine 10 in accordance with an embodiment ofthe present invention is depicted. In one form, engine 10 is an aircraftpropulsion power plant. In other embodiments, engine 10 may be aland-based or marine engine. In one form, engine 10 is a multi-spoolturbofan engine. In other embodiments, engine 10 may be a single ormulti-spool turbofan, turboshaft, turbojet, turboprop gas turbine orcombined cycle engine.

Gas turbine engine 10 includes a fan system 12, a compressor system 14,a diffuser 16, a combustion system 18 and a turbine system 20.Compressor system 14 is in fluid communication with fan system 12.Diffuser 16 is in fluid communication with compressor system 14.Combustion system 18 is fluidly disposed between compressor system 14and turbine system 20. Fan system 12 includes a fan rotor system 22. Invarious embodiments, fan rotor system 22 includes one or more rotors(not shown) that are powered by turbine system 20 and operative topressurize air. Compressor system 14 includes a compressor rotor system24. In various embodiments, compressor rotor system 24 includes one ormore rotors (not shown) that are powered by turbine system 20 andoperative to further pressurize air received from fan system 12. Turbinesystem 20 includes a turbine rotor system 26. In various embodiments,turbine rotor system 26 includes one or more rotors (not shown)operative to drive fan rotor system 22 and compressor rotor system 24.Turbine rotor system 26 is driving coupled to compressor rotor system 24and fan rotor system 22 via a shafting system 28. In variousembodiments, shafting system 28 includes a plurality of shafts that mayrotate at the same or different speeds and in the same or differentdirections. In some embodiments, only a single shaft may be employed.

During the operation of gas turbine engine 10, air is drawn into theinlet of fan system 12 and pressurized by fan system 12. Some of the airpressurized by fan system 12 is directed into compressor system 14, andthe balance is directed into a bypass duct (not shown) for providing acomponent of the thrust output by gas turbine engine 10. Compressorsystem 14 further pressurizes the air received from fan system 12, whichis then discharged in to diffuser 16. Diffuser 16 reduces the velocityof the pressurized air, and directs the diffused airflow into combustionsystem 18. Fuel is mixed with the pressurized air in combustion system18, which is then combusted. In one form, combustion system 18 includesa combustion liner (not shown) that contains a continuous combustionprocess. In other embodiments, combustion system 18 may take otherforms, and may be, for example, a wave rotor combustion system, a rotaryvalve combustion system, or a slinger combustion system, and may employdeflagration and/or detonation combustion processes. The hot gasesexiting combustion system 18 are directed into turbine system 20, whichextracts energy in the form of mechanical shaft power to drive fansystem 12 and compressor system 14 via shafting system 28. The hot gasesexiting turbine system 20 are directed into a nozzle (not shown), andprovide a component of the thrust output by gas turbine engine 10.

Referring to FIG. 2, combustion system 18 includes a combustion liner 30and a fuel injection system 32. Combustion liner 30 is disposed in acombustor case 34. Combustion liner 30 is operative to containcombustion processes during the operation of engine 10. Fuel injectionsystem 32 is operative to inject fuel into combustion liner 30. Inparticular, fuel injection system 32 is operative to inject a fuel/airmixture into combustion liner 30, which is ignited by an igniter (notshown) to form a combustion process 36 that adds heat to the airdischarged by compressor system 14. The heated air is then discharged bycombustion system 18 into turbine system 20.

Referring to FIG. 3 in conjunction with FIG. 2, fuel injection system 32includes a pilot injection module 38 and a main injection module 40.Main injection module 40 is disposed concentrically around pilotinjection module 38, i.e., radially outward of pilot injection module38. Pilot injection module 38, disposed radially inward of maininjection module 40, is configured inject a pilot fuel flow 42 togenerate a pilot combustion process 44. Main injection module 40 isconfigured to inject a main fuel flow 46 to generate a main combustionprocess 48 disposed around pilot combustion process 44. In one form,pilot injection module 38 and main injection module 40 are independentlyoperable. During low power operation of engine 10, e.g., includingground idle and flight idle conditions, pilot injection module 38 isemployed. Main injection module 40 is employed during high power engine10 operation, e.g., including take-off and cruise thrust. Some operatingregimes include the use of both pilot injection module 38 and maininjection module 40, e.g., during transition from idle or other lowpower conditions to higher power conditions. In some embodiments, bothmain injection module 40 and pilot injection module 38 may be employedto inject fuel into combustion liner 30 during high power engine 10operation. In other embodiments, only main injection module 40 isemployed during high power engine 10 operation.

Pilot injection module 38 is fluidly coupled to a fuel supply line 50.Main injection module 40 is fluidly coupled to a fuel supply line 52.Fuel supply lines 50 and 52 are fluidly independent of each other, thatis, one supply line may be pressurized to supply fuel to thecorresponding injection module independent of the other fuel supplyline. In one form, fuel injection system 32 is configured to selectivelycontrol fuel delivery (including fuel pressure) to fuel supply lines 50and 52, providing independent control of pilot injection module 38 andmain injection module 40 to selectively supply fuel to one or both ofpilot injection module 38 and main injection module 40. In otherembodiments, pilot injection module 38 and main injection module 40 maybe fluidly coupled to a common fuel supply line, and may be selectivelyand independently operable via other means. In still other embodiments,pilot injection module 38 and main injection module 40 may not beindependently operable as such. In one form, pilot injection module 38is optimized for operation in low engine 10 power conditions, and maininjection module 40 is optimized for operation in high engine 10 powerconditions. In other embodiments, pilot injection module 38 and maininjection module 40 may be optimized for operation at other engine 10power conditions.

Pilot injection module 38 includes a pilot nozzle 54, a pilot swirler 56and a discharge nozzle 58. Pilot nozzle 54 is in fluid communicationwith fuel supply line 50. Pilot nozzle 54 is operative to inject fuelinto combustion liner 30. In one form, pilot nozzle 54 is a pressureswirl atomizer. In other embodiments, pilot nozzle 54 may take otherforms. In one form, pilot swirler 56 surrounds pilot nozzle 54. In otherembodiments, pilot swirler 56 may be arranged in other locations andorientations. In one form, pilot swirler 56 includes a plurality ofturning vanes 60 configured to induce swirl into airflow passing throughpilot swirler 56. In other embodiments, other means for inducing swirlmay be employed, e.g., air injection and/or fuel injection portsconfigured to induce swirl.

The swirling pilot airflow from pilot swirler 56 mixes with the fuelsprayed by pilot nozzle 54. In one form, pilot injection module 38 isconfigured to mix pilot fuel spray and air before injection into thecombustion zone. The swirl induced by pilot swirler 56 enhances themixing of fuel and air for pilot injection module 38, e.g., relative tosystems that do not employ swirlers. The amount of swirl may vary withthe application. The fuel discharged from pilot nozzle 54 and the airpassing through pilot swirler 56 are discharged into combustion liner 30via discharge nozzle 58. In one form, discharge nozzle 58 is circular inshape. In other embodiments, discharge nozzle 58 may be shapeddifferently.

Main injection module 40 includes a main fuel injector 62, a mainswirler 64, a deswirler 66 and a discharge nozzle 68. Main fuel injector62 is in fluid communication with fuel supply line 52. Main fuelinjector 62 is operative to inject fuel for mixing with air andcombustion in combustion liner 30. In one form, main fuel injector 62 isconfigured to indirectly inject fuel into combustion liner 30, viaswirler 64. In other embodiments, main fuel injector 62 may beconfigured to directly inject fuel into combustion liner 30, e.g.,similar to pilot nozzle 54.

Main fuel injector 62 includes a fuel manifold 70 and plurality of mainfuel nozzles 72. In one form, manifold 70 is a distribution annulusformed in main fuel injector 62 and disposed radially outward of andcircumferentially around pilot injection module 38. In otherembodiments, fuel manifold 70 may take other forms. Fuel manifold 70 isin fluid communication with fuel supply line 52. Fuel nozzles 72 are influid communication fuel manifold 70. In one form, fuel nozzles 72 areplain-jet nozzles. In other embodiments, other nozzle types may beemployed in addition to or in place of plain-jet nozzles. In one form,nozzles 72 extend outward in a radial direction from manifold 70. In theexample depicted in FIG. 3, nozzles 72 extend both radially outward andaft. In other embodiments, nozzles 72 may extend in other directions inaddition to or in place of radial and/or aft directions. In one form,nozzles 72 are configured to discharge fuel radially outward, that is,having a radially outward flow direction component. In the exampledepicted in FIG. 3, nozzles 72 are configured to discharge fuel bothradially outward and aft. In other embodiments, nozzles 72 may beconfigured to discharge fuel in other directions in addition to or inplace of radial and/or aft directions. In some embodiments, some nozzles72 may be configured to discharge fuel in one direction, whereas othersmay be configured to discharge fuel in one or more other directions.

Main swirler 64 is configured to induce swirl in order to enhance themixing of fuel and air for main fuel injector 62. In one form, mainswirler 64 is an axial swirler. In other embodiments, main swirler 64may take one or more other forms. In one form, main swirler 64 includesa plurality of turning vanes 74 configured to induce swirl into airflowpassing through main swirler 64. In other embodiments, other means forinducing swirl may be employed, e.g., air injection and/or fuelinjection ports configured to induce swirl. In one form, nozzles 72include discharge openings 76 disposed in main swirler 64, and areoperative to inject fuel directly into main swirler 64. In otherembodiments, some or all of discharge openings 76 may be disposedelsewhere.

Deswirler 66 is configured to reduce swirl induced by main swirler 64.In one form, deswirler 66 is disposed radially outward of main swirler64. In other embodiments, deswirler 66 may be positioned in otherlocations and orientations. In one form, deswirler 66 includes anon-swirling air passage. In a particular form, deswirler 66 isconfigured to form an annular non-swirling air stream disposed aroundthe swirling fuel and air discharged by main swirler 64, to reduce theexit swirl angle of the fuel and air discharged through discharge nozzle68. In other embodiments, other means for reducing swirl may beemployed.

Discharge nozzle 68 is operative to discharge the air fuel mixture,generated by main injection module 40, into combustion liner 30. In oneform, discharge nozzle 68 is a converging nozzle. In other embodiments,discharge nozzle 68 may take other forms. In one form, discharge nozzle68 includes contraction ramps 80 and 82 extending to and forming athroat 84. In one form, ramps 80 and 82 are conical. In otherembodiments, ramps 80 and 82 may take other forms. In some embodiments,only a single contraction ramp may be employed. The air fuel mixturegenerated by main injection module 40 is injected into combustion liner30 via discharge nozzle 68. In one form, discharge nozzle 68 is annularin shape, extending concentrically around pilot injection module 38 anddischarge nozzle 58. In other embodiments, discharge nozzle 68 may takeother forms. In one form, ramps 80 and 82 are configured to direct theair fuel mixture from main injection module 40 in a radially outwarddirection, that is, in a direction having a radially outward componentfrom pilot injection module 38. In one form, discharge nozzle 68includes a plurality of air injection openings 86 spaced apartcircumferentially around the periphery of discharge nozzle 68, locatedaft of deswirler 66 and forward of contraction ramp 80. Air injectionopenings 86 are positioned to injection air into main injection module40 upstream of discharge nozzle 68. In other embodiments, air injectionopenings may be disposed in other locations. Air injection openings 86may take any convenient shape. Some embodiments may not include airinjection openings 86.

Disposed between pilot nozzle 54 and main injection module 40 is aseparating member 88. In one form, separating member 88 is configured asa heat shield to shield pilot nozzle 54 from heat generated during thecombustion of fuel.

Embodiments of the present invention include a gas turbine engine,comprising: a compressor system; a turbine system; and a combustionsystem fluidly disposed between the compressor system and the turbinesystem, the combustion system including a combustion liner and a fuelinjection system operative to inject fuel into the combustion liner,wherein the fuel injection system includes: a pilot injection modulehaving a pilot nozzle and a pilot swirler for the pilot nozzle, whereinthe pilot swirler is operative to induce swirl to enhance mixing of fueland air for the pilot injection module; and a main injection moduledisposed radially outward of the pilot injection module, wherein themain injection module includes a main fuel injector; a main swirler; anda deswirler, wherein the main fuel injector includes a plurality ofnozzles operative to discharge fuel radially outward; wherein the mainswirler is operative to induce swirl to enhance mixing of fuel and airfor the main fuel injector; and wherein the deswirler is operative toreduce swirl induced by the main swirler.

In a refinement, the deswirler is located radially outward of the mainswirler.

In another refinement, the main fuel injector includes a plurality ofplain-jet nozzles.

In yet another refinement, the engine further comprises a main fuelmanifold, wherein at least one of the plain-jet nozzles extends outwardin a radial direction from the main fuel manifold.

In still another refinement, at least one of the plain-jet nozzles has adischarge opening disposed in the main swirler.

In yet still another refinement, the engine further comprises a firstfuel supply line; and a second fuel supply line that is fluidlyindependent of the first fuel supply line, wherein the pilot nozzle isfluidly coupled to the first fuel supply line; and wherein the main fuelinjector is fluidly coupled to the second fuel supply line.

In a further refinement, the fuel injection system is configured toselectively supply fuel to one or both of the pilot injection module andthe main injection module.

Embodiments of the present invention include a fuel injection system fora gas turbine engine, comprising: a main injection module including aplurality of plain-jet nozzles; a main swirler; and a deswirler; whereinat least one of the plain-jet nozzles is operative to discharge fuelradially outward; wherein the main swirler is operative to induce swirlto enhance mixing of fuel and air for the main injection module; andwherein the deswirler is operative to reduce swirl induced by the mainswirler; and a pilot injection module disposed radially inward of themain injection module, wherein the pilot injection module includes apilot nozzle and a pilot swirler for the pilot nozzle, wherein the pilotswirler is operative to induce swirl to enhance mixing of fuel and airfor the pilot injection module.

In a refinement, the deswirler includes a non-swirling air passage.

In another refinement, the main injection module includes an annulardischarge nozzle for discharging a fuel air mixture.

In yet another refinement, the main injection module includes adischarge nozzle for discharging a fuel air mixture, further comprisinga plurality of air injection openings positioned to inject air into themain injection module upstream of the discharge nozzle.

In still another refinement, the system further comprises a rampconfigured to direct an air fuel mixture from the main injection modulein a radially outward direction.

In yet still another refinement, the ramp is conical.

In a further refinement, the system further comprises a separatingmember disposed around the pilot nozzle and positioned between the pilotnozzle and the main injection module.

In a yet further refinement, the separating member is configured toshield the pilot nozzle from combustion heat.

In a still further refinement, the at least one of the plain-jet nozzlesis configured to inject fuel directly into the main swirler.

Embodiments of the present invention include a fuel injection system fora gas turbine engine, comprising: a pilot injection module having apilot nozzle operative to produce a pilot combustion zone; and a maininjection module having a fuel distribution manifold; a plurality ofmain nozzles extending from the fuel distribution manifold for injectingfuel; a main swirler; and a deswirler, wherein the main swirler isoperative to induce swirl into fuel and air in the main injectionmodule; and wherein the deswirler is operative to reduce swirl inducedby the main swirler.

In a refinement, the system further comprises a heat shield disposedaround the pilot injection module and positioned between the pilotinjection module and the main injection module.

In another refinement, the main nozzles are plain-jet nozzles orientedwith a directional component extending radially outward of the pilotnozzle.

In still another refinement, the main injection module is configured toproduce a main combustion zone disposed radially outward of the pilotcombustion zone.

While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment(s), but on the contrary, is intended to covervarious modifications and equivalent arrangements included within thespirit and scope of the appended claims, which scope is to be accordedthe broadest interpretation so as to encompass all such modificationsand equivalent structures as permitted under the law. Furthermore itshould be understood that while the use of the word preferable,preferably, or preferred in the description above indicates that featureso described may be more desirable, it nonetheless may not be necessaryand any embodiment lacking the same may be contemplated as within thescope of the invention, that scope being defined by the claims thatfollow. In reading the claims it is intended that when words such as“a,” “an,” “at least one” and “at least a portion” are used, there is nointention to limit the claim to only one item unless specifically statedto the contrary in the claim. Further, when the language “at least aportion” and/or “a portion” is used the item may include a portionand/or the entire item unless specifically stated to the contrary.

1. A gas turbine engine, comprising: a compressor system; a turbinesystem; and a combustion system fluidly disposed between the compressorsystem and the turbine system, the combustion system including acombustion liner and a fuel injection system operative to inject fuelinto the combustion liner, wherein the fuel injection system includes: apilot injection module having a pilot nozzle and a pilot swirler for thepilot nozzle, wherein the pilot swirler is operative to induce swirl toenhance mixing of fuel and air for the pilot injection module; and amain injection module disposed radially outward of the pilot injectionmodule, wherein the main injection module includes a main fuel injector;a main swirler; and a deswirler, wherein the main fuel injector includesa plurality of nozzles operative to discharge fuel radially outward;wherein the main swirler is operative to induce swirl to enhance mixingof fuel and air for the main fuel injector; and wherein the deswirler isoperative to reduce swirl induced by the main swirler.
 2. The gasturbine engine of claim 1, wherein the deswirler is located radiallyoutward of the main swirler.
 3. The gas turbine engine of claim 1,wherein the main fuel injector includes a plurality of plain-jetnozzles.
 4. The gas turbine engine of claim 3, further comprising a mainfuel manifold, wherein at least one of the plain-jet nozzles extendsoutward in a radial direction from the main fuel manifold.
 5. The gasturbine engine of claim 3, wherein at least one of the plain-jet nozzleshas a discharge opening disposed in the main swirler.
 6. The gas turbineengine of claim 1, further comprising a first fuel supply line; and asecond fuel supply line that is fluidly independent of the first fuelsupply line, wherein the pilot nozzle is fluidly coupled to the firstfuel supply line; and wherein the main fuel injector is fluidly coupledto the second fuel supply line.
 7. The gas turbine engine of claim 1,wherein the fuel injection system is configured to selectively supplyfuel to one or both of the pilot injection module and the main injectionmodule.
 8. A fuel injection system for a gas turbine engine, comprising:a main injection module including a plurality of plain-jet nozzles; amain swirler; and a deswirler; wherein at least one of the plain-jetnozzles is operative to discharge fuel radially outward; wherein themain swirler is operative to induce swirl to enhance mixing of fuel andair for the main injection module; and wherein the deswirler isoperative to reduce swirl induced by the main swirler; and a pilotinjection module disposed radially inward of the main injection module,wherein the pilot injection module includes a pilot nozzle and a pilotswirler for the pilot nozzle, wherein the pilot swirler is operative toinduce swirl to enhance mixing of fuel and air for the pilot injectionmodule.
 9. The fuel injection system of claim 8, wherein the deswirlerincludes a non-swirling air passage.
 10. The fuel injection system ofclaim 8, wherein the main injection module includes an annular dischargenozzle for discharging a fuel air mixture.
 11. The fuel injection systemof claim 8, wherein the main injection module includes a dischargenozzle for discharging a fuel air mixture, further comprising aplurality of air injection openings positioned to inject air into themain injection module upstream of the discharge nozzle.
 12. The fuelinjection system of claim 8, further comprising a ramp configured todirect an air fuel mixture from the main injection module in a radiallyoutward direction.
 13. The fuel injection system of claim 12, whereinthe ramp is conical.
 14. The fuel injection system of claim 8, furthercomprising a separating member disposed around the pilot nozzle andpositioned between the pilot nozzle and the main injection module. 15.The fuel injection system of claim 14, wherein the separating member isconfigured to shield the pilot nozzle from combustion heat.
 16. The fuelinjection system of claim 8, wherein the at least one of the plain-jetnozzles is configured to inject fuel directly into the main swirler. 17.A fuel injection system for a gas turbine engine, comprising: a pilotinjection module having a pilot nozzle operative to produce a pilotcombustion zone; and a main injection module having a fuel distributionmanifold; a plurality of main nozzles extending from the fueldistribution manifold for injecting fuel; a main swirler; and adeswirler, wherein the main swirler is operative to induce swirl intofuel and air in the main injection module; and wherein the deswirler isoperative to reduce swirl induced by the main swirler.
 18. The fuelinjection system of claim 17, further comprising a heat shield disposedaround the pilot injection module and positioned between the pilotinjection module and the main injection module.
 19. The fuel injectionsystem of claim 17, wherein the main nozzles are plain-jet nozzlesoriented with a directional component extending radially outward of thepilot nozzle.
 20. The fuel injection system of claim 17, wherein themain injection module is configured to produce a main combustion zonedisposed radially outward of the pilot combustion zone.